Textile machine with at least one service unit

ABSTRACT

The invention relates to a textile machine with at least one first service unit ( 14   a   , 14   b ) capable of traveling along a guide rail alongside a plurality of processing stations of the textile machine, and with a control system ( 20   a   , 20   b   ; 22 ) for the control of the travel movement of the service unit ( 14   a   , 14   b ). According to the invention the control system ( 20   a   , 20   b   ; 22 ) can make data on travel path delimitations ( 18 ), predetermined return points and/or obstacles ( 14   a - d ) available, and the control system ( 20   a   , 20   b   ; 22 ) controls the travel movement in function of the data of the travel path delimitations ( 18 ), the predetermined return points and/or the obstacles ( 14   a - d ).

[0001] The present invention relates to a textile machine with a controlsystem to control the travel movement, whereby the service unit iscapable of being moved along a guide rail alongside a plurality ofprocessing stations of a textile machine to service and/or control theprocessing stations.

[0002] In a known open-end spinning machine (DE 31 11 627 A1) twodifferent service units can be moved on a guide rail alongside aplurality of identical spinning stations. One of the service units has atravel obstacle signaler for each direction of travel, connected to atravel direction-reversing device. Each time a travel obstacle signalermeets an obstacle, the travel direction-reversing device reverses thetravel direction of the service unit. In this process a bodily“detection by scanning” of obstacles along the traveling path takesplace, and the reversal of the direction of travel is initiatedindependently of the nature of the obstacle.

[0003] In another known open-end spinning machine (DE 199 30 644 A1)identical service units can be moved alongside a plurality of spinningstations along a guide rail of the open-end spinning machine. A sensorrecording an obstacle on the travel path and initiating the reversal ofthe direction of travel of the service unit at the occurrence of suchobstacles is proposed in this case for each service unit. Thereby acollision of the service units with each other is also avoided.

[0004] It is the object of the invention to provide a textile machinewith at least one service unit and a process for same making it possibleto control the movement of the service unit in a flexible and efficientmanner while taking into account obstacles or operating zones. Thisobject is attained through the characteristics of claims 1, 10 or 22.

[0005] Advantageous embodiments are indicated in the sub-claims.

[0006] According to claim 1, at least one first service unit can bemoved along a guide rail alongside a plurality of processing stations ofa textile machine. The service unit carries out maintenance functionsand/or control functions on the processing stations. The travelingmovement of the service unit is controlled by a control system. Data oftravel path limits, predetermined return points and/or obstacles can bestored in the control system, e.g. in a memory from which they can becalled up. The control system takes into account the stored data ontravel path limits, predetermined return points and/or obstacles as itcontrols the travel movement.

[0007] Service units are in this case regular robots performingdifferent tasks at the processing stations of the textile machine,cleaning robots, etc. Such tasks are e.g. the cleaning of theworkstations, the return to the workstation in case of a malfunction orthe presentation of initial products etc. In an open-end spinningmachine the replacement of bobbins is in addition carried out e.g. by apiecing robot when a bobbin has been filled with spun yarn, or piecingis effected at the spinning station in case of yarn breakage.

[0008] An obstacle in the sense of this application is an obstacle thatis “known” to the textile machine. For this data concerning the “known”obstacle are made available in a control system or through theinteraction of several control systems. Such an obstacle is herenormally another service unit, a service station of a service unitoccupied at the moment by a service unit, a spinning station beingserviced that cannot be passed, an obstacle determined as such by a dataentry, etc. An obstacle of this kind therefore need not be detectedwithout contact or through physical contact through the intermediary ofa detection device, but the presence of such an obstacle is construed onbasis of already existing data. The detection devices operating withoutcontact or through contact detect unknown obstacles that are also takeninto account in controlling the travel movement. A maintenance worker onthe travel path is for example such an unforeseen obstacle.

[0009] A return point is here normally any pre-determined point alongthe guide rail over which the service unity could physically move. Thereturn point is determined by means of data entry by the control systemor e.g. by an operator.

[0010] A travel path limit is here normally the end point of the guiderail or an additional, optional component on a textile machineindicating the fixed end of the travel path of the service unit beforewhich the service unit is preferably decelerated already during itsapproach.

[0011] By making data available on obstacles, travel path limits and/orpredetermined return points, the travel movement control can be adjustedto these in a flexible and efficient manner since travel of the serviceunit is not simply continued until a physical or contact-less detectionof the actual presence of an obstacle takes place.

[0012] If a control system of the service unit and/or of the textilemachine is used to control the travel movement, the travel path controlcan be implemented by an already existing control unit. The hierarchicaldivision of the travel path control is broken down preferably inadaptation to the existing, hierarchical division of the control units.Thus for example, the travel movement control of a service unit is takenover by its control system, whereby the latter is made available data onother service unites, travel path limits or predetermined return pointsthrough the control system of the textile machine (central machinecontrol). Or else the travel movement control is taken over through thecontrols of the textile machine, e.g. the central machine control, sothat only movement commands are transmitted from the latter to thecontrol system of the service unit. Or else only distance data and dataconcerning the type of obstacle are provided by the central machinecontrol, so that the control system of the service unit initiatesadditional control measures under inclusion of additional data such ase.g. the position and/or the speed of the service unit.

[0013] In an especially advantageous embodiment, the data concerning atleast one second service unit are made available. As a result of thisthe travel movement control of the first service unit can be coordinatedwith the second service unit. This is especially advantageous when oneside of the textile machine is assigned at least two or three serviceunits on a permanent basis. Since all service units service processingstations adjoining each other or are able to service them, the danger ofcollision between service units is especially great. Since the serviceunits approach each other frequently, the mechanical constraint causedby rapid braking before the other service unit would be especiallygreat, and this would result in increased wear of a carriage of theservice unit. By providing data on the other service unit it is thuspossible to take appropriate measures, e.g. soft braking, already in theapproach zone.

[0014] The data, e.g. position, speed etc., are preferably transmittedamong the service units via the communication channel between eachservice unit and the central machine control (control unit of thetextile machine). It is however also possible for the data to beexchanged among the service units, and for every service unit to thencarry out the travel movement control in accordance with the exchangeddata. Such a data exchange can be effected via an optical communicationschannel between the service units.

[0015] In the process for the control of travel movement according toclaim 10, the travel movement is controlled in function of dataregarding travel path limits, predetermined return points and/orobstacles, whereby these date are provided by a control system. The dataalso contain the type of obstacle so that obstacle-specific can be takeninto account in the control of the travel movement. Therefore no blind“feeling around” the travel path takes place, nor do any avoidancemovements of the service unit occur that are not dependent on obstacles.

[0016] On order to treat the carriage of the service unit with care,braking is initiated preferably in function of the current speed of theservice unit and the distance from the obstacle.

[0017] Thanks to the knowledge of the type of obstacle, e.g. a merelypassing obstacle such as another service unit, the further travelbehavior of the service unit can be rendered dependent upon the type ofan obstacle once it has been ascertained. If it is learned from the dataof the obstacle that it will soon no longer be present, it may sufficefor example to merely slow down the movement of the service unit in thedirection of the obstacle. Or else the service unit may be stoppedbefore the obstacle to remain there in readiness until the obstacle hasleft.

[0018] Preferably the work status of a second service unit is alsotransmitted together with the other data, so that it may be ascertainedwhich travel movement the first service unit carries out next, based onthe work status of the two service unit. Thereby the operatingefficiency of the first service unit is increased. The latter reversesits direction of travel for example if the second service unit is activefor a longer period of time at a processing station. If the secondservice unit remains only for a short time at the processing station,e.g. to blow-clean a spinning station of a rotor spinning machine, thefirst service unit can wait for the end of the activity of the secondservice unit and continue its travel thereafter.

[0019] In the process according to claim 22 the data regarding thepredetermined operating zones of a first and a second service unit canbe obtained and the control of the travel movement takes place infunction of these obtained data. For each service unit, its own workzone is thereby managed. Here more than two service units can beprovided, with the work zone of each being defined in the control systemfor each service unit. The details regarding service units, controlsystem, etc. described earlier apply here accordingly.

[0020] If one of the service units is taken out of operation the areagoing from the border zone of the work zone of the other service unit tothe position of the service unit taken out of operation of the otherservice unit is added for maintenance and/or control of the processingstations. The service unit may be out of operation because it was takenout of operation, because a defect has occurred in the service unit,because the control of the service unit has failed, because some serviceis being performed on the service unit, because the textile machine isnot yet in operation, etc. A state in which the service unit is unableto determine its present position or cannot transmit the presentposition to the control system (control system of the service unitand/or of the textile machine) is considered to be out of operation. Inthe latter case the service unit is preferably stopped and remains inits position.

[0021] The position of the service unit taken out of operation is eitherdetected by it and is transmitted to the control system, or thatposition is assumed to apply in which the last position message wastransmitted from the service unit to the control system. In addition tothe software-controlled avoidance of collision between the first and thesecond service unit, a detection device is preferably provided for anobstacle (see below) by means of which the service unit which is now outof operation can be detected in case that the last announced orcurrently announced position does not coincide with the actual position.

[0022] The current position of the service unit taken out of operationis advantageously detected by a detection device or is transmitted by anoperator to the control system. A detection device for the detection ofthe position of the service unit taken out of service may e.g. belocated at the service unit that is in operation.

[0023] I the first as well as the second service unit is out ofoperation, such as may be the case when the textile machine is switchedon again, the absolute position of the two service units is at firstunknown. In order to avoid a collision, the operating zone of theservice unit first taken into operation is determined only within thezone over which the service unit first taken into operation was movedinto its initialization position without collision with the otherservice unit. If both service units are for example at the same end ofthe overall operating zone of processing stations, and if theinitialization position of one service unit is at the other end, theservice unit, as it travels to the other end, determines that all theprocessing stations located between the two ends can be approachedwithout collision, so that initially this entire zone of the firstinitialized service unit is determined to be its operating zone.

[0024] The operating zone of a service unit in operation or of a serviceunit first put into operation can be extended or reduced by thoseprocessing stations around which the other, not yet operative serviceunit is moved, e.g. during the travel of the other, not yet operativeservice unit to its initialization position. For each service unit aninitialization position or a plurality of initialization positions to beapproached as desired can thereby be provided. The absolute position ofthe service unit at the textile machine is determined in oneinitialization position. In an initialization displacement a serviceunit is preferably moved into the direction opposite to the direction ofthe other service unit. The initialization displacement can be initiatedby the control system or by an operator. The service unit can also bepushed by the operator without using the drive of the service unit.

[0025] The course of travel or the relative position of a service unittaken out of operation is detected by means of position markings or bydetection devices along the travel path of the service unit, whereby thedirection of travel is also detected.

[0026] Only once both service units have been initialized, i.e. whentheir absolute position at the textile machine has been determined, arethe original operating zones of each service unit released once more.

[0027] The embodiments of the invention are explained in further detailthrough drawings.

[0028]FIG. 1 shows a schematic top view of a rotor spinning machine withtwo piecing robots per spinning machine side,

[0029]FIG. 2 shows a schematic side view of two piecing robots capableof traveling on a common guide rail,

[0030]FIG. 3 shows a schematic side view of two piecing robots with acontact switching device,

[0031]FIG. 4 shows a side view in perspective of two piecing robots withlaterally installed detection devices,

[0032]FIG. 5a shows the determination of the operating zone of a serviceunit in operation when a second service unit is out of operation, and

[0033]FIG. 5b shows the determination of an operating zone when twoservice units are out of operation.

[0034]FIG. 2 shows a schematic side view of the piecing robots 14 a-d.In each of the piecing robots 14 a, 14 b a control unit 20 a, 20 b isprovided that is connected via a communications connection 21 a, 21 b toa central machine control or spinning machine control system 22 of therotor spinning machine 10. The communications connection 21 a, 21 b canbe a data conduit for example, contained together with the supplyconduits in the drag chain.

[0035] In the upper area of each of the piecing robots 14 a, 14 b aswitching unit 23 is provided in which a switching hoop 24 is pivotallymounted. The switching hoop 24 protrudes laterally from the piecingrobots and extends in its lower part over the width of the piecingrobots. The switching hoop 24 can be swiveled towards the piecing robot.The switching hoops 24 serve to detect a lateral obstacle such as e.g.an operator 26 of the rotor spinning machine 10 as sketched in FIG. 2.By swiveling the switching hoop 24 slightly towards the inside aswitching contact is established in the switching unit 23 and thepiecing robots 14 a, 14 b is braked. Furthermore additional switchingsteps beyond the first contact point are provided when the switchinghoop 24 is swiveled further. Thereby a second switching contact isactuated as the switching hoop 24 is swiveled further inward, causingincreased deceleration of the piecing robot. Finally, when the switchinghoop is swiveled completely inward, a third switching contact isactuated, resulting in the abrupt stopping of the piecing robot. Inaddition an emergency stop switch button 25 that also causes the abruptstopping of the piecing robot when encountering an obstacle or whenactuated by an operator 26 is provided on each piecing robot.

[0036] The data on the absolute positions of the piecing robots (seebelow) determined in the control unit 20 a, 20 b or in the spinningmachine control system 22 are exchanged, so that the relative distancebetween two piecing robots can be calculated through the absoluteposition information. Thereby the distance from another piecing robotwhich also represents an obstacle on the travel path due to the commontravel path along the guide rail is detected. The distance between apiecing robot 14 a-d from an obstacle, e.g. from an empty-bobbin feedingdevice 18, is calculated in the same way.

[0037]FIG. 3 shows a second embodiment of an obstacle-detecting deviceserving to avoid a collision between the piecing robots 14 a, 14 b. Hereswitches 30 are provided in the right upper lateral area of the piecingrobots 14 a, 14 b (in the side view of FIG. 3), and these switches aretriggered by pins or projections 31 on the facing side of the adjoiningpiecing robot. The switch 30 and the pin 31 are provided as alternativesto the emergency stop switch button 25 and the switching hoop 24 of FIG.2, or in addition to the emergency stop switch button 25 and/or theswitching hoop 24. In the latter case a redundant detection device forthe avoidance of collisions is made available for the case that theemergency stop switch button 25 and/or the switching unit 23 connectedto the switching hoop 24 would not be triggered. The switches 30 areconnected to the control units 20 a, 20 b that monitor the switchingsignal of the switches 30 and cause the stopping of the piecing robotsat the appearance of a signal. A switch as well as a pin 31 isadvantageously provided on each side of the piecing robot, so thatcollision monitoring is effected for either direction of travel for eachpiecing robot 14 a, 14 b.

[0038]FIG. 4 shows a lateral view in perspective of the piecing robots14 a, 14 b. On the lateral surfaces of each of the piecing robots 14 a,14 b a transmission unit 40, a reflector 41 and a receiver 42 areprovided side by side. The transmission unit 40 emits a light signal atan angle to the vertical of the lateral surface. At a given distancebetween the piecing robots 14 a, 14 b the ray coming from thetransmission unit 40 that is bundled in the direction of the room meetsthe 41 of the facing piecing robot. From there the light ray isreflected at the angle of incidence and is thrown back to the emittingpiecing robot 14 b. There, the light ray reaches the receiver 42. As aresult the receiver 42 only receives the signal emitted by thetransmission unit 40 when a defined distance is kept between the piecingrobots 14 a, 14 b. In order to avoid that the receiver 42 be influencedby a signal from the opposite transmission unit 40, the detection of thesignals is wavelength-dependent, whereby a differenttransmitting/receiving frequency is used for each side of a piecingrobot 14 a-d. Alternatively the signals have different modulation infunction of the side of the piecing robot, so that the receiver 42 onlydetects the signal emitted on the same side from the correspondingtransmission unit 40.

[0039] With this arrangement the piecing robot 14 b can also detect theposition of the piecing robot 14 a and vice versa. This possibility ofposition detection can also be used for a robot to signal the positionof a robot (see below) out of service to the control unit 20 a, 20 band/or to the spinning machine control system 22. If the central machinecontrol 22 does for example not know the position of the piecing robot14 a, it can cause the piecing robot 14 b to find that position. Withthe reception of this position signal the travel movement control of thepiecing robot 14 a can be resumed.

[0040] In addition to or in lieu of the transmitting/receiving unit 40,42 of FIG. 4, a distance detection unit (not shown) can be provided suchas is known e.g. from motion detectors. Here too thetransmission/receiving frequency varies depending on the side of thepiecing robot 14 a-d, so that the distance detection units across fromeach other will not influence each other. The distance signal can beevaluated in a discrete manner, whereby a signal above a given signalintensity is emitted. In this case a collision avoidance process wouldbe triggered when the distance falls below a predetermined minimum.Alternatively the distance from the respective obstacle or the facingspinning robot is not in steps but continuously, so that adistance-dependent collision avoidance process can be initiated.

[0041] In one mode of collision avoidance control an obstacle and thedistance to the obstacle are recorded by means of the distance detectionunit. By scanning the data on the end points of the travel path (e.g.empty-bobbin feeding device 18) and on the positions of the otherpiecing robots 14 a-d in the control unit 20 a, 20 b, 22 it is foundthat this is an unforeseen obstacle, e.g. an operator 26. In order toprevent interference with the operator 26 caused by the approachingpiecing robot 14 a-d, the piecing robot is moved only up to apredetermined distance from the obstacle. The distance is calculated insuch manner in this case that the operator 26 may not feel rushed by thepiecing rotor and is able to perform his service work undisturbed.

[0042] The described detection devices for the avoidance of collisioncan be provided in any desired combination with each other. Thus forexample, a distance detection sensor 40, 41, 42 according to FIG. 4 witha switching hoop 24 and a emergency stop switch button 25 according toFIG. 2, or similar arrangement. By combining two or more detectiondevices per travel direction the reliability of obstacle detection isincreased. Here the position and distance determination between apiecing robot 14 a-d and an obstacle by means of a control unit 20 a, 20b, 22 or by means of the interaction of the control units serves toavoid a collision with the obstacles “known” to the spinning machine.Here appropriate measures can be initiated for the soft braking of thepiecing robot before the obstacle and/or the controlled approach of therobot to the obstacle. The detection devices 23, 24; 25; 40, 41. 42described above which detect an obstacles by contact or without contactserve above all to recognize “unforeseen” obstacles and intervene alsowhen defects occur in the determination of the obstacles by means of thecontrol unit 20 a, 20 b, 22.

[0043] The signals transmitted by the detection devices are used withdifferent priorities in the control of the movement of the piecingrobots 14 a, 14 b. The signal of the emergency stop switch button 25 forexample, circumvents the control unit 20 a, 20 b, 22 and resultsdirectly to drive of the piecing robot being switched off or braked. Thefirst two steps of the switching unit 23 are evaluated with highpriority by the respective control unit 20 a, 20 b for the braking ofthe piecing robot. A corresponding status message is transmitted to thecontrol unit 22. On the other hand the position or distance signalssupplied by the control unit 20 a, 20 b and/or 22 are taken into accountwith low priority.

[0044] Braking, stopping and temporary waiting after stopping and/or thereversal of the direction of travel of piecing robot 14 a-d arecontrolled by the control unit 20 a, 20 b of the piecing robots 14 a-dand/or by the spinning machine control system 22 in function of the typeof signal received by the detection device. When the signal of aemergency stop switch button 25, of the third step of the switching hoop24 and the switching unit 23 appears, or if a distance detection device(40, 41, 42) has detected that a minimum safety distance is not reached,the piecing robot is stopped immediately and remains in the stoppedposition until it is again put into operation with a release signal,e.g. upon verification by an operator 26. The distance signal with theminimum safety distance can here be provided also by the control units21 a, 21 b, 22, by the transmission/receiving unit 40, 42 or by anotherdistance sensor as described above.

[0045] The piecing robot can be braked in function of the distance fromthe obstacle with greater deceleration as the distance decreases. If inthat case the obstacle, e.g. another piecing robot, moves again awayfrom the piecing robot, the latter can continue its travel withouthaving to stop completely. However the piecing robot can also wait for apredetermined time span in its position after stopping to ascertainwhether the obstacle moves away within a predetermined waiting timebefore it reverses its direction of travel. Thereby the spinningstations 13 are not left without service for any length of time in thedirection of travel that was the robot's before braking. This is becausedue to the reversal of travel direction the service unit no longerchecks the spinning stations in the original direction of travel, butthose that are now in the opposite direction of travel. It may thenstill be possible that a spinning station requiring servicing cannot beapproached if it is located on the path in the direction of the originaldirection of travel, shortly after the point of reversal.

[0046] Especially in the case in which position data are made availablevia the control units 21 a, 21 b, 22 concerning other piecing robots 14a-d and/or reversal points as well as end points in the travel path of apiecing rotor, the reaction to an obstacle can be controlled in functionof the obstacle itself. Thus for example, end points can be approachedwith the minimum distance to an obstacle not being observed. In FIG. 1for example, the piecing robot 14 can be moved to a point directly infront of the empty-bobbin feeding device 18 even though a signal of adistance sensor signals an obstacle. When a return point is prescribed,the travel path of a piecing robot is predetermined by an arbitrarilyprescribed position along the travel rail 15, 16, whereby the returnpoint is not a physical end of the travel path. Such an end point isdetermined by one of the control units 20 a, 20 b or 22 or by anoperator and can be defined freely.

[0047] When an obstacle is detected within an approach distance and itis recognized through the data comparison that it is another piecingrobot, a predetermined minimum distance that may be greater than thesafety distance from some other obstacle is observed. This ensures thattwo piecing robots, whereby one may be waiting at a piecing station 13,do not interfere with each other. The minimum distance could be e.g. thesection width of 10 piecing stations 13.

[0048] If the service function fails in one of the piecing robots 14 a-dso that it is no longer available for service at a spinning station 13,the piecing robot is moved to its starting position (for initialization,see below) or to a maintenance position. If the latter is not availableor if another piecing robot must pass this location, an avoidancefunction of the deactivated piecing robot is actuated. The deactivatedpiecing robot then avoids an approaching piecing robot via the distancerecognition system while observing a minimum distance. The minimumdistance can be e.g. a section width of 10 piecing stations, and iscancelled when the defective piecing robot can no longer move away inavoidance direction because of some other obstacle, e.g. theempty-bobbin feeding device 18.

[0049] The control units 20 a, 20 b or the spinning machine controlsystem 22 constantly monitor or calculate the current position of thepiecing robots 14 a, 14 b. This takes place either through aninitialization of the position of the piecing robot in its startingposition, at which a position counter is installed at a fixed positionalong the guide rail 15, 16, and the position is then calculated basedon the travel path distance covered, or else position markings areprovided along the guide rails 15, 16 so that a detection device (notshown) can detect the current position of the piecing robot 14 a-dconcerned. The initialization may take place in a basic position or inseveral basic positions optionally selected. The determination ofpositions can also be effected through a combination of initialization,travel path determination and position comparison at the positionmarkings. In this case a position counter is reset in an initializationin the fixed starting position and the distance covered is determinedfrom that point. The latter takes place through detection of positionmarkings along the guide rails or a calculated value of the currentposition is compared to the detected position. As a rule the positionmarkings are relative markings, so that the service unit detects adistance covered based only on the relative position markings. Theposition markings may however also be absolute markings, so that theservice unit is able to detect at each marking the absolute position atthe textile machine. In the latter case the service unit can be moved toany position marking for initialization.

[0050] If the determination of the position of one of the piecing robots14 a-d is not made by the control units 20 a, 20 b, 22, the piecingrobot remains at its position until the initialization in the startingposition as described above can again be effected and determination ofposition is again ensured.

[0051]FIG. 5a shows the situation of the piecing robots 14 a and 14 bwhen the piecing robot 14 b has been taken out of operation. The piecingrobot 14 b could have been taken out of operation by an operator forinstance, the travel controls could no longer be functioning or positiondata may no longer be available, so that the piecing robot 14 b wasstopped because of the missing position data. The normal operating zonesA and B assigned respectively to the two piecing robots 14 a and 14 b inoperation are assigned to the other piecing robot when one is no longerin operation. In FIG. 5a the operating zone of the piecing robot 14 a isextended from A to A′. In this case it is assumed that the piecing robot14 b which is out of operation is stopped at the position at which ithas last transmitted its latest position data, in case that these can nolonger be detected. Alternatively the piecing robot 14 a taken out ofoperation transmits its current position data if it is still able todetect them.

[0052] The extended operating zone A′ of the piecing robot 14 a is sizedso that a sufficient safety distance from the piecing robot 14 b isobserved, and so that no collision between the piecing robots may occur.The distance is preferably sufficiently great so that mutual influenceby piecing robots 14 a, 14 b approaching each other too closely isreliably avoided. The distance is e.g. equal to one section width or to10 spinning stations. To initialize the robot 14 b that has been takenout of service, i.e. to find its absolute position on the guide rail 15,the piecing robot 14 b is moved away by the robot 14 a which is still inoperation and into the initialization position I1. The determination ofabsolute position takes place in the initialization position I1. Theinitialization travel of the piecing robot 14 b into initializationposition I1 is caused either by the control unit 20 b or 22 or by anoperator. In this case the piecing robot 14 b can also be moved manuallyinto the initialization position I1. If the piecing robot 14 b is stillable to record the covered distance or the position marking along thetravel path during this initialization travel it can transmit these tocontrol unit 20 b or 22. The control unit then extends continuously theoperating zone A′ of the piecing robot 14 a by the distance covered bythe robot 14 b. If the initialization position I1 is located outside thearea of the spinning stations, all the spinning stations on thatspinning machine side can thus be covered by the extended operating zoneA′.

[0053] Every piecing robot 14 has here its own initialization positionI1, I2 or several initialization positions. To initialize the respectivepiecing robot the initialization travel is initiated in such manner thatthe piecing robot moves away from the closest piecing robot also capableof servicing his operating zone. If on the other hand the piecing robot14 b that has been taken out of service is pushed in the direction ofthe piecing robot 14 a that is in operation, e.g. by an operator, thedistance covered by the piecing robot 14 b is detected and the operatingzone of the piecing robot 14 a is decreased by that distance.

[0054]FIG. 5b schematically shows a situation in which the two piecingrotors 14 a, 14 b are not yet initialized. This is the case e.g. afterfirst start-up of the spinning machine 10. In this case neither theposition of the piecing robot 14 a nor of the piecing robot 14 b is asyet known. To put the piecing robot 14 b into operation, it is movedinto the initialization position I1. During this initialization travelit covers the distance B′ without encountering an obstacle. It can thusbe assumed that the segment B′ is a zone that can be freely traveled andthis segment is defined as operating zone B′ of the piecing robot 14 bthat it can service after initialization. Here too the distance B′covered during the initialization travel was detected, e.g. throughposition markings. Until the second piecing robot 14 a has also beeninitialized in its initialization position I2 and the normal operatingzones A, B can be assigned to the piecing robots 14 a, 14 b, the piecingrobot 14 b services the operating zone B′. As described above regardingFIG. 5a, the operating zone B′ of the piecing robot 14 b can be extendedduring the initialization travel of the piecing robot 14 a toinitialization position I2 by the distance covered by the piecing robot14 a, or can be reduced when the piecing robot 14 a is moved towards thepiecing rotor 14 b.

[0055] Instead of measuring the covered travel distance or the relativeposition of a piecing robot taken out of operation, an operator can alsoenter the position of the piecing robot taken out of operation into thecontrol unit. Sensors can however also be provided along the travel pathto sense the piecing robot and to transmit the position of the piecingrobot to the control unit 20 a, 20 b, 22 (e.g. central machine control).

[0056] Optionally the control unit can make available data for maximumadmissible operating zones of the piecing robots. Information on maximumadmissible operating zones are either preset permanently on the spinningmachine or can be prescribed e.g. by an operator. The maximum admissibleoperating zones may for example coincide with the operating zones A, Bin FIG. 5a. In this case the temporarily determined operating zones A′and B′ in FIGS. 5a and 5 b are shorter or at the most as long as theoperating zones A and B. Such limits can be set as described abovebilaterally or only unilaterally in one direction.

1. Textile machine with t least one first service unit traveling along aguide rail (15, 16) alongside a plurality of processing stations (13) ofthe textile machine (10) for the servicing and/or control of theprocessing stations (13), and a control system to control the travelmovement of the service units (41 a-d), characterized in that data oftravel path delimitations (18), predetermined return points and/orobstacles (14 a-d) can be entered into the control system (20 a, 20 b;22) and in that the control system (20 a, 20 b; 22) controls the travelmovement in function of the data of the travel path delimitations (18),of the predetermined return points and/or of the obstacles (14 a-d). 2.Textile machine as in claim 1, characterized in that travel data of thefirst service unit (14 a-d) can be entered in the control system (20 a,20 b; 22), in particular the direction of travel, the position on theguide rail (15, 16), the dimensions of the first service unit and/or thespeed of the first service unit (14 a-d).
 3. Textile machine as in claim1 or 2, characterized in that the control system (20 a, 20 b; 22) isassigned to the service unit (14 a-d) and/or to the textile machine (10)for the control of the travel movement.
 4. Textile machine as in claim1, 2 or 3, characterized in that information on one or several endpoints (18) of the travel path of the service unit (14 a-d) can bestored in the control system (20 a, 20 b; 22).
 5. Textile machine as inclaim 5, characterized by a communications system (20 a, 20 b, 21 a, 21b, 22) to make the data of the second service unit (14 a-d) available.6. Textile machine as in claim 6, characterized in that thecommunications system (20 a, 20 b, 21 a, 21 b, 22) is a transmissionsystem for communication between the first service unit (14 a-d) and thesecond service unit (14 a-d) and/or a transmission system (21 a, 21 b)for communication between the control system (20 a, 20 b) of the serviceunit (14 a-d) and the control systems (22) of the textile machine (10).7. Textile machine as in claim 6, characterized in that thecommunications system (20 a, 20 b, 21 a, 21 b, 22) is a transmissionsystem for communication between the first service unit (14 a-d) and thesecond service unit (14 a-d) and/or a transmission system (21 a, 21 b)for communication between the control system (20 a, 20 b) of the serviceunit (14 a-d) and the control system (22) of the textile machine (10).8. Textile machine as in claim 5, 6 or 7, characterized in that the dataregarding the at least second service unit (14 a-d) one or more pointsof the following information: The position, the direction of travel, thedimensions of the second service unit and/or the speed of the secondservice unit.
 9. Textile machine as in one of the preceding claims,characterized in that the textile machine (10) has one or more detectiondevices (23, 24; 25; 30, 31; 40, 41, 42) making available data on one orseveral temporary obstacles (26) to the control system (20 a, 20 b; 22).10. Process for the control of the travel movement of a first serviceunit (14 a-d) capable of traveling along a guide rail (15, 16) alongsidea plurality of processing stations (13) of a textile machine (10) forservicing and/or control of the processing stations (13)1, characterizedin that the control of the travel movement takes place in function ofdata regarding the travel path delimitations (18), predetermined returnpoints and/or obstacles (14 a-d), whereby the data are made available bya control system (20 a, 20 b; 22).
 11. Process as in claim 10,characterized in that the control of the travel path control takes placein function of data provided by the first service unit (14 a-d), inparticular in function of the position, the direction of travel, thedimensions of the first service unit and/or the travel speed of thefirst service unit.
 12. Process as in claim 10 or 11, characterized inthat braking, stopping and/or reversal of the first service unit (14a-d) take place in function of the distance between the first serviceunit (14 a-d) and the travel path delimitation (18), of thepredetermined return point and/or on the obstacle (14 a-d) and/or thespeed of the first service unit.
 13. Process as in claim 12,characterized in that the braking force increases as the distancedecreases and/or increases proportionally to the speed of the firstservice unit (14 a-d).
 14. Process as in one of the claims 10 to 13,characterized in that the first service unit (14 a-d) stops or reversesits course upon detecting an obstacle (14 a-d).
 15. Process as in one ofthe claims 10 to 14, characterized in that the data of the secondservice unit (14 a-d) are made available and the first service unit (14a-d) is controlled in function of the data of the second service unit.16. Process as in claim 15, characterized in that the data of the secondservice unit (14 a-d) include: the position, the direction of travel,the travel speed, the dimensions of the second service unit and/or theoperating status of the second service unit.
 17. Process as in one ofthe claims 10 to 16, characterized in that a minimum distance is keptbetween the service units by using a signal indicating the distance froma second service unit (14 a-d) and/or of position data of the firstservice unit (14 a-d) and of a second service unit.
 18. Process as inone of the claims 10 to 17, characterized in that the absolute positionof the first service unit (14 a-d) and/or of a second service unit (14a-d) results from an initialization at a predetermined position alongthe guide rail (15, 16).
 19. Process as in claim 18, characterized inthat the current position of the first and/or of the second service unit(14 a-d) is determined on basis of the distance covered, the speedand/or based on absolute and/or relative position markings along thetravel path.
 20. Process as in one of the claims 10 to 19, characterizedin that when the control and/or service function of the first serviceunit (14 a-d) is deactivated, the first service unit eludes a secondservice unit (14 a-d) by observing a minimum distance.
 21. Process as inclaim 20, characterized in that the minimum distance between the firstand the second service unit (14 a-d) is decreased when the secondservice unit is unable to elude an obstacle (14 a-d) because of a travelmovement delimitation (18).
 22. Process for the control of travelmovement control of a first and at least one second service unit (14a-d) capable of traveling along a common travel path alongside aplurality of processing stations (13) of a textile machine (10) toservice and/or control the processing stations (13), characterized inthat the travel movement control of the first and second service unitstakes place in function of data of operating zones (A, B) to bepredetermined of the first and second service unit, whereby these dataare made available by a control system (20 a, 20 b; 22).
 23. Process asin claim 22, characterized in that when the first service unit (14 b) isout of operation, the operating zone (A′) of the second service unit (14a) is extended up to the present or last reported position of the firstservice unit (14 b).
 24. Process as in claim 23, characterized in thatthe current position of the first service unit (14 b) is transmitted tothe control system (20 a, 20 b; 22) by a detection device or by anoperator.
 25. Process as in claim 22, characterized in that when thefirst and the second service unit (14 a, 14 b) are out of service, theoperating zone of the second service unit is determined to be the zonealong which the second service unit has been moved without collision upto an initialization position (I1, I2).
 26. Process as in claim 23, 24or 25, characterized in that during the movement of the first serviceunit, in particular while the first service unit is traveling to aninitialization position (I1, I2), the operating zone (B′) of the secondservice unit (14 b) is extended or reduced by the distance covered bythe first service unit (14 a).
 27. Process as in claim 28, characterizedin that the distance covered is ascertained by means of travel pathdetection and/or detection of position markings and/or detection devicesalong the travel path and by means of detection of the direction oftravel.
 28. Process as in claim 27, characterized in that a positionmarking is provided at every processing station.
 29. Process as in oneof the claims 23 to 28, characterized in that the operating zones (A, B)of the first and the second service units (14 a, 14 b) are freed oncethe first service unit has been initialized in an initializationposition and has been taken back into operation.
 30. Process as in oneof the claims 22 to 29, characterized in that a temporarily determinedoperating zone (A′, B′) of the first and/or second service unit (14 a,14 b) is limited to a maximum admissible operating zone (A, B). 31.Process as in one of the claims 22 to 30, characterized in that thetravel movement of the first and/or the second service unit (14 a, 14 b)is controlled during maintenance and/or control of the processingstations (13) in the normal operating zone (A, B) and/or in thetemporarily designated operating zone (A′, B′) in accordance with one ofthe claims 10 to
 21. 32. Textile machine with at least two service units(14 a, 14 b) and a control system (20 a, 20 b; 22), characterized inthat a process according to one of the claims 22 to 30 is implemented.